Repeater strike mechanisms are exceptional timepieces, as regards their large number of components and the care and time required for fabrication and assembly operations. Striking mechanism complications have been known since at least the XVIII century, but have only been the subject of a limited number of publications between 1763 and the middle of the XX century. The reference work best known to the practitioner of complications, in particular grand strikes and repeaters, to which reference will be made to avoid overloading the presentation of the invention, is the work “Les montres compliquées” (Complicated watches) by François Lecoultre and edited by Editions Horlogères in Bienne.
Often, the space available inside complicated timepieces, in particular watches, is such that it is not possible to duplicate certain functions, in particular acoustic functions, inside the case, and a choice therefore has to be made between acoustic and/or musical functions.
More specifically, the alarm function is a separate complication from the grand strike or minute repeater complications.
EP Patent Application No. 1925 997 A1 in the name of CHRISTOPHE CLARET SA discloses a striking mechanism controlled by a cam shaft, with locking after the striking mechanism has been operated, and including a silencer with a bolt for locking the control member. The striking mechanism includes an energy source for driving the racks and a gear train connecting the energy source to a regulating member. The racks are kinematically connected to the energy source via a striking mechanism drive device arranged in the gear train and activated by a control member. The racks are intended to cooperate with snails to extract information regarding the current time. The control member is a cam shaft provided with at least one cam cooperating with the drive device via at least one connecting element and at least one drive wheel set for pivoting said cam when the striking mechanism is released.
FR Patent Application No 537 399 A in the name of RIGOULOT discloses a three-quarter striking mechanism activated by a single rack on the hour repeater, and able to be adapted to an alarm movement with a repeater striking mechanism. The main striking mechanism sounds the hours and the quarters. The position of a lever is changed by the action of a snail for the hour and the quarters, and the hours and quarters are struck in the hour repeater using a mobile pin, via a single rack.
EP Patent No. 1 708 051 A1 in the name of ZENITH INTERNATIONAL SA discloses an alarm mechanism that can be uncoupled. It includes an energy source which is locked when the mechanism is at rest and unlocked when it is operating. It includes a setting system for programming the strike time. It includes a release system comprising a control member which governs the unlocking of the energy source, and a cam kinematically connected to the movement and performing one revolution in twenty-four hours. It includes a striking mechanism driven by said energy source, and provided with a hammer for striking a gong or an object that does not resonate. The control member is provided with an arm which ends in a first catch, and the cam includes a single notch for receiving said catch in order to unlock the energy source.
FR Patent No 455 174 A, in the name of BORDONI GUGGERI, discloses an alarm mechanism which includes a device automatically striking the hours and quarters with hour and quarter repeaters. It includes a toothed sector and a rack, replacing the hour snail, and elastically connected to a strike wheel. The toothed sector moves forward by one tooth when the mechanism prepares the hour strike for the next blow, and the forward movement is produced by stopping the rack on the periphery and by lowering the arbour thereof. There is a pause between the hour strike and the quarter strike owing to a transmission ratio selected to give an additional strike, which is stopped by a bent lever releasing the quarter hammer.
CH Patent Application No. 252 169A in the name of PAILLARD discloses a timing device including an operating member which can tip, held in two positions by a spring, and an activating member which, after a time determined by the position of an adjusting member, causes the operating member to tip from one of its two positions to the other.